Energy Aware Resource Allocation for Incremental AF-OFDM Relaying

This letter first presents an incremental amplify-and-forward orthogonal frequency division multiplexing relaying scheme to promote the spectrum efficiency of cooperative transmission. Then, the energy efficiency problem is thoughtfully investigated in order to prolong the lifetime for such battery-operated wireless networks. As will be seen, the original optimization problem incorporating incremental policy, relay selection and power loading is formulated as a mixed-integer nonlinear programming problem that is quite hard to solve even numerically, thereby necessitating our derivation of a suboptimal approach for implementation feasibility. Specifically, by exploiting energy pricing concept as well as max-min energy efficiency criterion, a stepwise energy aware resource allocation algorithm is proposed. Finally, numerical results verify the benefits of our proposals.